In people's impression, gravure printing uses solvent based ink, which not only pollutes a lot but also does not comply with environmental regulations. Therefore, many printing factories have switched from gravure printing to flexographic printing. Of course, some printing factories have also changed from solvent based ink to water-based ink for use. So, can water-based ink be used in gravure printing?
Gravure printing can use water-based ink, but multiple factors need to be considered to ensure printing effect and quality. The following is a detailed explanation of the use of water-based ink in gravure printing:
1、 Characteristics and advantages of water-based ink
characteristic:
Environmental friendliness: Water based ink uses water as the solvent, does not contain toxic organic solvents, is harmless to the environment and human health, and meets modern environmental protection requirements.
Safety: Water based ink is non flammable and non explosive, reducing safety hazards in the workplace.
Printing effect: The patterns printed with water-based ink are fine and the colors are bright, which can meet the high-quality requirements of gravure printing.
Advantages:
Cost reduction: Compared with solvent based inks, water-based inks have lower usage costs, which helps to reduce printing costs.
Easy to clean: Water based ink is easy to clean, reducing maintenance costs for printing equipment and tools.
2、 Precautions for using water-based ink in gravure printing
Choose the appropriate model:
The gravure printing machine needs to choose a model suitable for using water-based ink, including water-resistant coating rollers, printing plates, and drying equipment.
The printing plate is usually made of electro engraved or laser plate, with a plate depth between 15 μ and 20 μ to improve printing speed and avoid water ripple phenomenon.
Choose the appropriate water-based ink:
The selection should be based on factors such as printing materials, type of water-based ink, and printing speed.
Different substrates have different requirements for water-based inks, for example, plastic films may need to undergo electrical discharge treatment before printing to increase surface tension.
Adjust the appropriate printing conditions:
Adjust parameters such as temperature, humidity, pressure, and speed to ensure printing quality.
Due to the relatively slow drying speed of water-based ink, special attention should be paid to the selection and adjustment of drying equipment, and the drying temperature should be determined according to the different substrates and the size of the printing area.
Pay attention to the maintenance of ink:
Maintain the stability and quality of ink to avoid deterioration and contamination.
Regularly check the viscosity, pH value and other performance indicators of ink to ensure that it is in the best condition.
Operations during the printing process:
Before printing, pour ink into the ink tank and let the printing plate idle for 2-3 minutes to wet and stir the plate.
During the printing process, when it is necessary to stop printing in order to observe the printed product, the printing plate should not be allowed to stop rotating to avoid plate clogging caused by dry stock.
Before printing, adjust the printing viscosity according to the depth of the plate, and try not to add tap water during the printing process. Just add new ink with consistent viscosity.
Post printing processing:
After printing, the printing plate should be cleaned immediately. Pour ink into the bucket and cover it. Put clean water into the ink tank and rotate the printing plate for cleaning or mix it with a 3% laundry detergent solution for cleaning.
3、 The application prospects of water-based ink in gravure printing
With the increasing global awareness of environmental protection and the increasingly strict environmental regulations, water-based inks have broad prospects for application in gravure printing. It can not only meet the market's demand for environmentally friendly products, but also improve the quality and efficiency of printed materials. With the continuous advancement of technology and the upgrading of printing equipment, it is believed that the application of water-based ink in gravure printing will become more extensive and in-depth.
In summary, gravure printing can use water-based ink, but it is important to choose the appropriate model, ink, and printing conditions, and follow the correct operating steps and maintenance methods. Only in this way can the advantages of water-based ink be fully utilized to achieve high-quality gravure printing effects.